The nominal capacity of sealed lead acid battery is calculated according to JIS C8702-1 Standard with using 20-hour discharge rate. For example, the capacity of WP5-12 battery is 5Ah, which means that when the battery is discharged with C20 rate, i.e., 0.25 amperes, the discharge time will be 20 hours.
1. Construction of sealed lead acid batteries Positive plate: Pasting the lead paste onto the grid, and transforming the paste with curing and formation processes to lead dioxide active material. The grid is made of Pb-Ca alloy, and the lead paste is a mixture of lead oxide and sulfuric acid.
If you need 24 Volts, you can connect two group 21 batteries in series to double the voltage. The voltage of a series connection is equal to the sum of the voltages of all its batteries. If one 12V lead-acid battery is connected to another 12V lead-acid battery, you have 24V total power output.
The electrical energy is stored in the form of chemical form, when the charging current is passed. lead acid battery cells are capable of producing a large amount of energy. The construction of a lead acid battery cell is as shown in Fig. 1. It consists of the following parts : Anode or positive terminal (or plate).
3.3 Battery Self-discharge The lead acid battery will have self-discharge reaction under open circuit condition, in which the lead is reacted with sulfuric acid to form lead sulfate and evolve hydrogen. The reaction is accelerated at higher temperature. The result of self-discharge is the lowering of voltage and capacity loss.
Various capacity parameters of lead-acid batteries are: energy density is 60-75 Wh/l, specific energy is 30-40 Wh/Kg, charge/discharge efficiency is 50-92%, specific power is 180 W/kg, self discharge rate is 3-20%/month, cycle durability is 500-800 cycles and nominal cell voltage is 2.105 V . ... [...] ...